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In a heat engine, if 700J of heat enters the system, and the piston does 400J of work, what is the final internal thermal energy of the system if the initial energy is 1200J?

1 Answer

3 votes
Hello!

Answer:

1500 J

Step-by-step explanation:

We are going to use the first law of thermodynamics which can be summarized as:

Δ
U=Q-W

U2-U1=Q-W

So, we have that:


U1=1200j \\ W=400 \\ Q=700j


U2=Q-W+U1

By substituting we have:


U2=700 J - 400 J + 1200J=1500J

Have a nice day :)





User Kostia Mololkin
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